Many people often opt for pine trees when adding trees to landscape designs. They are evergreen, low maintenance, can last for hundreds of years, and are also highly sought after for commercial timber. Unfortunately, despite all the positives, pine trees are vulnerable to breakage and uprooting.
Pine trees fall over easily because they are tall and have shallow roots. The roots are also not expansive nor firm enough to protect pine trees against strong winds and storms. Pine root collar weevils also damage root systems, making them weak and vulnerable while standalone trees fall easily.
I’ll discuss why pine trees fall over in more detail. I’ll also give you some ideas on what you can do to keep your pine trees from falling.
Why Pine Trees Fall Over Easily
When exposed to strong winds and storms, all trees are at risk of falling over. However, some, like pine trees, are more vulnerable. In 2012, Hurricane Sandy brought down thousands of trees, including century-old pine trees.
Pine trees fall over easily for various reasons.
Shallow Root System
The roots of a tree are not only crucial for providing nourishment, but they also anchor the tree. The roots of pine trees are naturally short and weak. The tree’s tap root may be twice the height of the tree but the root system is shallower.
The fibrous roots lie about 12 inches (30.48 cm) beneath the soil’s surface. When they grow without interference, the roots spread to about twice the tree’s height. Strong winds easily uproot the shallow roots. They also easily loosen from the soil during floods, making it easy for them to fall over.
Urbanization and its effects, such as the construction of buildings and roads, often interferes with the growth of pine tree roots. Unsurprisingly, New York lost over 10,000 pine trees to Hurricane Sandy.
Y or V-Shaped Trunks
As pine trees grow tall, they start branching out as the limbs compete to see which will become dominant. While these Y and V-shaped sections of the tree may contribute to the beauty of the tree, they also weaken it.
The twin branches are heavy and will pull the tree to one side in the event of high winds, winter storms, or floods.
Substantial Canopy
Pine trees fall under evergreen trees. They shed old leaves but retain a substantial amount of leaves at the top all year round. This is unlike deciduous trees, which shed off their leaves during fall. Unfortunately, the top-heavy pine trees are quite vulnerable to strong winds.
Pine Trees Are Tall
Pine trees can grow to a height of between 65 and 250 feet (19.8 m – 76.2 m), depending on the species. Even in a forest, the pine tree is usually one of the tallest trees.
Shorter trees have the protection of taller trees during a storm. Unfortunately, this means the tall pine trees are more vulnerable to extreme weather conditions because they don’t enjoy the protection that shorter trees do.
| Pine Tree Species | Height |
| Italian Cypress | 65 feet (19.8 m) |
| White spruce | 70 feet (21.3 m) |
| Ponderosa pine | 100 feet (30.5 m) |
| Scots pine | 130 feet (39.6 m) |
| European larch | 140 feet (42.7 m) |
| Western red cedar | 200 feet (70 m) |
| Douglas fir | 250 feet (76.2 m) |
Soil Saturation
The physical limitations of pine trees are not always responsible for their fall. Sometimes, the soil type and its condition increase the trees’ vulnerability. Soil saturation and poorly draining soils can also cause pine trees to topple.
Roots growing in sandy soil are typically not firm. Saturated soils also weaken roots, causing pine trees to fall over during floods.
Standalone Pine Trees
A forest of pine trees is safer from windthrow. Unfortunately, most people grow one or two pine trees due to space limitations. Standalone pine trees stand no chance against strong winds. They will fall over because they are in the path of fast winds.
Pine trees grown closely together easily slow strong winds. They also cause the wind to change direction, blowing over the trees instead of hitting the trunks and uprooting them.
Pine Root Collar Weevils
Pests, like the pine root collar weevils, also weaken pine trees. This makes it easy for pine trees to fall over. Pine root collar weevils destroy Scots pine, Austrian pine, Eastern white pine, and red pine. However, the Eastern white pine is least resistant to these pests because they have a lot of sap.
The larva stage is the most destructive. The creamy white larvae are legless and sport a reddish brown head. A fully grown larva is 14-17 mm (0.55-0.70 in) long.
The larvae bore underneath the tree’s bark (cambial region) and feed on the inner part of the bark. They focus on the root collar region, and this is where they get their name. They feed on the tree extensively, reducing the size of the tree beneath the soil line. The tree becomes weak, causing it to tip over quickly. Additionally, the weevils slow the movement of nutrients and water to the leaves and branches.
Adult pine root collar weevils are 9-12 mm (0.35-0.47 in) long. They are dark brown and black, with tiny, white specks across their bodies. Their stout beaks curve downwards, making it easy for them to chew tree barks.
Signs of pine root collar weevil infestation include;
- Yellowing and drying leaves
- The tree’s base starts swelling and turning black
- Loose soil around the tree’s base
- The tree starts leaning to one side
- Long-term infestation causes the entire tree to start drying. It will turn brown and eventually die
Pine root collar weevils usually attack trees 2 – 20 feet (0.61 – 6.1 m) tall. Trees with a small diameter (an inch or less) are less vulnerable to attacks.
You should drench the area around the tree with Compare-N-Save Bifenthrin Concentrate (available on Amazon.com) if you notice pine root collar weevil damage. A mid-May application will kill hibernation adults and keep them from laying eggs. The second application in mid-August will target newly hatched adults.
This video gives tips on how to identify pine tree problems, including pest attacks.
Signs Your Pine Tree Is at Risk of Falling Over
Pine trees are more prone to falling when exposed to high winds and storms. However, some pine trees fall, even without nature’s help. You should occasionally inspect your pine trees to confirm if you should cut them down before they destroy your property.
Some telltale signs of a weak pine tree include
- A leaning tree
- Pine tree with multiple trunks, creating a Y or V-shaped trunk
- Falling tree branches
- Mushrooms growing at the tree’s base. This is a sign of water saturation and loosening soil
- Nearby trees have recently fallen
- When you dig around the root collar, you’ll find it’s black and soaked in pitch.
You also need to pay attention to signs of pest infestation. Early identification of pine tree vulnerability will help you act before strong winds bring the tree down, probably causing it to fall over your house.
Tips on How To Keep Pine Trees From Falling Over Easily
The physical characteristics of pine trees put them at a significant disadvantage against strong winds and heavy rains. However, you can take several measures to give your pine trees a fighting chance.
- Prune the pine trees regularly to keep them from developing weak Y or V-shaped trunks.
- Maintain your pine trees to keep them from growing to their maximum height. Shorter pine trees are less likely to fall over.
- Don’t plant your pine trees too close to one another because they will have thin trunks which cannot withstand strong winds.
- Plant pine trees in well-draining soil.
- Avoid pruning trees during the rainy season because pests and diseases will take advantage of the open wounds.
- Avoid planting pine trees deep into the soil. Ensure the root collar is above the soil line as this protects them from pine root collar weevils.
- Regularly prune the lower branches to improve light penetration and air circulation at the tree’s base.
- Weed the area around the tree.
- Plant the trees in areas where they are sheltered from high winds.
Conclusion
Pine trees are great because they remain green, irrespective of the season. However, if your region is at risk of experiencing extreme weather conditions, such as hurricanes, it is best not to have them.
Since weather patterns are sometimes unpredictable, it is best to play it safe. Plant pine trees away from buildings, and ensure to control their height. If you notice signs of loose soil and a weakening tree, you should bring down the tree before nature does it for you.
